Precautions for the surface of food bag ink imprint

The ink imprinted surface on the surface of the substrate is determined by the transfer amount of the ink and the breakage of the ink film.It is the result of the joint action of factors such as the crack state and the drying degree of the link material. Ink self-printingThe transfer from the machine to the surface of the printing carrier is the mechanical behavior of ink splitting and transferring. inkThe split and transfer are completed in an instant, and the force it receives is a periodic impact.And the job period is very short and the strength is very high. When the ink viscosity is at the right value, the transfer amount isThe pressure relationship between the contact part of the printing plate and the impression cylinder of the printing press, the printing substrate and the printing plateThe ink flow speed between the plates and the shear rate of the ink between the printing plate and the paper are determined. shear stressIt plays an important role in the splitting and transfer of ink. When various raw materials appear in the printing processWhen the printing is interrupted, the pressure of the impression cylinder is removed, and the printing plate stops to the surface of the carrier.The surface transfers ink, the stable state of the printing process is destroyed, and the inking system stops supplying ink.When reprinting, the ink adhering to the ink roller is redistributed to the substrate sheet.The amount of ink transferred on the surface is small, and after several times of printing, the thickness of the ink layer reaches the positive value.constant value. The transfer of the ink film between the printing plate and the surface of the substrate is a near-impact action.The elastic effect is extremely significant. Because the ink film has aSex and ElasticityTherefore, the transfer of the ink film is not the entire amount of ink on the printing plate, but only one of thepart. With the distance created by the movement of the printing press and the substrate, the initial connection between the twoThe contact is displaced, and the distance between the printing plate and the substrate is caused by the displacement of the contact point.A gap is created, the ink film will be stretched, thinned, and a few smaller voids will appear. such littleThe appearance of a small amount of voids means that the ink film has begun to rupture, and the ink will spread to the surface of the substrate.The transfer of the face begins. At this time, the two sides of the ink film are still on the printing plate and the printing carrier respectively.superior. As the distance between the two increases, the ink film will continue to stretch and become thinner.The void in the middle will be bigger and more numerous. When this distance is increased to the maximum, the plate and paperThe displacement component between the sheets is completely greater than the elastic force of the ink film, and the middle part is stretched continuously.Thinner and finer ink film voids begin to break at the edges and may appear cylindrical at the breakShaped, or conical, or pointed. The surface state that constitutes the ink imprint on a microscopic scale. The state of the ink imprinted surface and the dryness of the ink vehicle itself, the ink tonedegree, ink layer thickness, number of overprints, printing time, substrate surface state, substrate moisture contentIt is related to factors such as quantity, ambient temperature and humidity. High-speed production conditions in printing multi-colorAnd many production enterprises can not provide constant temperature and humidity under the production environment constraints, the connectionThe drying degree of the material cannot meet the requirements of composite drying on the surface of the printed product, oftenIt is because the drying is not enough, the imprint is virtual or the surface is crystallized.